66 lines
2.0 KiB
Markdown
66 lines
2.0 KiB
Markdown
notigen
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=======
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OpenStack-like notification generator.
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It works like this: In OpenStack an operation is a series of notifications
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connected by a common request_id. For example, to create an instance we would
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have the following events:
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compute.run_instance.start
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scheduler.run_instance.start
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scheduler.run_instance.scheduled
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scheduler.run_instance.end
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compute.instance.update
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compute.instance.update
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compute.instance.update
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compute.instance.update
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compute.instance.update
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compute.instance.update
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compute.run_instance.end
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But, since this is a large system, we could have lots of these operations
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going on currently. Each operation takes time to perform. So the
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notifications generated by these operations are interleaved.
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This library simulates these many concurrent operations. You tell
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the EventGenerator how many new operations to start per minute
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and it will. Note that you'll get a lot more notificationis than
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the operations/second (since the operations persist over time in the
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future).
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The library tries to avoid bad sequences (like doing an update on
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a deleted instance), but it can happen in some race conditions.
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You can generate in real-time by passing in a real datetime or
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you can generate the events as fast as possible by incrementing
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a starting time by the tick amount. See the examples below.
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To generate events in real-time ...
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g = notigen.EventGenerator(100) # Number of operations per minute
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now = datetime.datetime.utcnow()
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start = now
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nevents = 0
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while nevents < 10000:
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e = g.generate(now)
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if e:
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nevents += len(e)
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now = datetime.datetime.utcnow()
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To generate events as fast as possible ...
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g = notigen.EventGenerator(100) # Not really relevant
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now = datetime.datetime.utcnow()
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start = now
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nevents = 0
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while nevents < 10000:
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e = g.generate(now)
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if e:
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nevents += len(e)
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now = g.move_to_next_tick(now)
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Datetimes are returned as strings as OpenStack would.
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